Focus Change Ordering Plan

Summary

• Current focus notifications use a single focus-changed signal; listeners derive focus state by comparing against FocusManager:get-focused-node.
• Listener execution order is undefined, so blur handlers can run after focus handlers and clobber state (e.g. inputs toggling text/normal).
• Ordered blur → focus signals make focus transitions deterministic, so widgets can respond only to their own event without checking global focus state or other widgets.

Planned Change

• Replace the single focus-changed signal with ordered notifications:
  • focus-blur (old node losing focus)
  • focus-focus (new node gaining focus)
• Blur must always fire before focus for the same transition.
• Remove the legacy focus-changed signal and update all listeners to the new API.

Migration Notes

• Update widgets that listen to focus changes (Input, Terminal, any focus-aware UI) to subscribe to the ordered signals.
• Ensure state transitions triggered on focus are only performed in the focus handler; blur should only perform cleanup.
• Keep the two-phase contract consistent across scene and HUD focus scopes.
• Once ordered signals are in place, remove the interim guard logic added to Input that checks for another active input before forcing :normal.

Follow-ups

• Add tests that assert blur fires before focus for a transition.
• Update any debug tooling or HUD status panels that show focus state.